Get started with Claude

Make your first API call to Claude and build a simple web search assistant.

Prerequisites

A Claude Console account
An API key

Call the API

1
Set your API key
Export your API key as an environment variable. The SDK reads ANTHROPIC_API_KEY automatically.
export ANTHROPIC_API_KEY="your-api-key-here"

Create a project and install the SDK

mkdir claude-quickstart && cd claude-quickstart
python3 -m venv .venv && source .venv/bin/activate
pip install anthropic

Create your code

Create a file called quickstart.py:

Python

import anthropic

client = anthropic.Anthropic()

message = client.messages.create(
    model="claude-opus-5-5",
    max_tokens=1000,
    messages=[
        {
            "role": "user",
            "content": "What should I search for to find the latest developments in renewable energy?",
        }
    ],
)

for block in message.content:
    if block.type == "text":
        print(block.text)

Run your code

python quickstart.py

Output

Here are some effective search strategies to find the latest developments in renewable energy:

## General Search Terms
- "Renewable energy news 2025"
- ...